Urban Tree Canopy and Environmental Justice: Examining the Distributional Equity of Urban Tree Canopy in Guangzhou, China.

Rapid urbanization has led to a series of environmental problems that are harmful to the physical and mental health of residents. Not only can increasing urban tree canopy (UTC) improve sustainable city development, but it can also effectively promote the quality of life for residents; however, the uneven spatial distribution of UTC can also bring about social justice problems. Currently, there are few studies related to the justice of UTC distribution in China.

[Evaluation of the heavy metals contamination and its potential ecological risk of the sediments in Beijiang River's upper and middle reaches].

In order to find out the heavy metals concentrations and their potential ecological risks of the sediments in Beijiang river's upper and middle reaches, 25 sediments specimens were sampled from both the trunk stream and tributaries for analyzing Cu, Pb, Zn, Cd, Ni, Cr, As and Hg. The Index of Geoaccumulation and the Potential Ecological Risk Index were then employed to evaluate the pollution degree of heavy metals in the sediments. The results indicate that the sediments in Beijiang River have been severely contaminated by many heavy metals.